174 The Commercial Apple Industry 



gated districts usually will average twice as many to the 

 acre as under the same conditions in the East ; that is, a 

 ten-year-old orchard in Wenatchee will have from 80 to 

 100 trees to the acre, while in New York 40 to 50 trees 

 would be considered sufficient. A fully matured orchard 

 in the northwestern regions will usually cpntain as many 

 as 75 trees to the acre, while the New York growers claim 

 that 30 trees is sufficient. Thus the trees of the North- 

 west do not attain such large size although they grow more 

 rapidly and attain maturity more quickly. 

 ■- 5. Trees of the irrigated regions have a shorter life 

 than those under natural or un-irrigated conditions. 

 Although most irrigated sections are as yet young, there 

 are definite evidences that the irrigated orchard 'is much 

 shorter lived than the eastern plantation. Trees that 

 attain maturity at such an early age under artificial condi- 

 tions cannot continue to maintain vegetative vigor and 

 health indefinitely. As yet it cannot be said just what 

 the life of an irrigated orchard under good management 

 may be, but from present indications it would seem that 

 thirty years would about mark the life of the average irri- 

 gated orchard. It is certain that trees are ordinarily most 

 profitable and at their best under irrigated conditions 

 between the ages of ten and twenty years. 



6. Irrigated regions are usually free from fungus. Se- 

 rious trouble only appears in the semi-irrigated regions like 

 Hood River Valley where the rainfall is as great as that in 

 western New York, but where orchards generally are under 

 irrigation, due to the rainfall coming at the wrong season 

 of the year. There is little fungus difficulty in the 

 famous Yakima and Wenatchee valleys of Washington or 

 in the irrigated districts of Idaho, Colorado, Utah and 



